The Normalized Difference Vegetation Index (NDVI) compares how much red and near-infrared light a patch of ground reflects. Healthy, chlorophyll-rich vegetation absorbs red light and strongly reflects near-infrared, giving high NDVI values (close to +1); bare soil, water and pavement give low or negative values. Beekeepers and land managers use satellite NDVI time-series, layered in a GIS, to predict where flowering forage will actually be available around a candidate apiary site — long before they ever visit in person.
A single honey bee colony can forage across several square kilometres, but because flight is energetically expensive, the overwhelming majority of foraging trips stay within about 1–2km of the hive — which is exactly why fine-grained NDVI maps close to a candidate site matter more than distant, larger patches.
A stylised satellite NDVI raster rendered in 3D: tile height and colour encode vegetation greenness, a translucent ring marks a candidate apiary's flight range, and a live forage score responds as you move the site and the season.
NDVI turns satellite red/near-infrared reflectance into a greenness index. Overlaying that raster with a hive's practical flight radius, and weighting by flight distance, is exactly how a GIS-based siting workflow scores a candidate apiary.
Drag the site sliders to relocate the apiary, resize the forage radius, and scrub through the day of year to watch spring green-up and autumn dieback shift the score. Raise the NDVI cutoff to see how much of the range still counts as good forage.
Because flight is metabolically costly, most foraging trips stay within roughly 1–2km of the hive even though bees can range several kilometres — so fine-grained NDVI near the site usually matters more than distant lush patches.